Chen Jing, Fan Wenfang, Zhang Tao, Tang Chaojun, Chen Xingyu, Wu Jingjing, Li Danyang, Yu Ying
Opt Express. 2017 Feb 20;25(4):3675-3681. doi: 10.1364/OE.25.003675.
We present a powerful method to enhance the magnetic plasmon (MP) resonances of metamaterials composed of periodic arrays of U-shaped metallic split-ring resonators (SRRs) for high-quality sensing. We show that by suspending the metamaterials to reduce the effect of the substrate, the strong diffraction coupling of MP resonances can be achieved, which leads to a narrow-band mixed MP mode with a large magnetic field enhancement. It is also shown that for such a diffraction coupling, the magnetic field component of the lattice resonance mode of periodic arrays must be parallel to the induced magnetic moment in the metallic SRRs. Importantly, the sensitivity and the figure of merit (FOM) of the suspended metamaterials can reach as high as 1300 nm/RIU and 40, respectively. These results suggest that the proposed metamaterials may find great potential applications in label-free biomedical sensing.
我们提出了一种强大的方法，用于增强由U形金属开口环谐振器（SRR）的周期性阵列组成的超材料的磁等离子体（MP）共振，以实现高质量传感。我们表明，通过悬浮超材料以减少衬底的影响，可以实现MP共振的强衍射耦合，这会导致具有大磁场增强的窄带混合MP模式。还表明，对于这种衍射耦合，周期性阵列的晶格共振模式的磁场分量必须与金属SRR中的感应磁矩平行。重要的是，悬浮超材料的灵敏度和品质因数（FOM）分别可高达1300 nm/RIU和40。这些结果表明，所提出的超材料在无标记生物医学传感中可能具有巨大的潜在应用。
